"We'd certainly believe that he's making his way back over there but there's been no confirmed sighting of him at this stage," he said.

"So certainly people on the main traffic routes or public transport should be aware and should they come into contact with him or see a person of that description, just let us know and we'll take all the necessary action from there.

Acting Superintendent Shields says Herbert has a "history of violence" and it is concerning that he managed to break free of his electronic monitoring device.

Herbert's mother, Ruth Herbert, has pleaded with her son to turn himself in.

She told Channel Nine she is desperate to hear from him.

"Jason, please. I beg you my love. Please contact me and let me know you are fine," she said.